Each oxyacid contains at least one unit

CHEMISTRY · Single correct

Problem

Each oxyacid contains at least one

X\text{-}OH

unit, where

X

is a non-metal. The H atom of the

X\text{-}OH

unit is ionisable, and the number of

\text{-}OH

groups directly attached to the non-metal decides the basicity of the oxyacid. Which of the following oxyacids can exhibit tautomerism? (1)

\mathrm{H_2N_2O_2}

(2)

\mathrm{H_4P_2O_6}

(3)

\mathrm{H_2S_2O_6}

(4)

\mathrm{H_3PO_3}